A shaped charge essentially comprises a main charge (bursting charge) with a conical cavity provided with a liner. The main charge is ignited by a detonator through a propagating charge. For optimum guidance of the detonation waves, a detonation waveguide or "barrier" is disposed in the propagating charge. (See German patent publications 34 08 865 A1, 32 16 684 C2 and 34 28 488 A1).
Shaped charges are manufactured by various methods. An integrated pressing method is known in which all components are pressed in a suitable mold. A barrier made of aluminum, for example, can thus be incorporated in the shaped charge. However, plastics or foams, which make much better damping materials, cannot be processed in this manner since they would sustain mechanical damage because of the high pressure.
For this reason, preformed parts (main charge, propagating charge, barrier) are generally used which need only be united with (e.g., adhesive-bonded to) one another in a mold, for example. (See German patent publication 28 52 358 C2).
It is know that a shaped charge has to be manufactured with high precision and that its axial symmetry should not be flawed if considerable losses in performance are to be avoided. Especially when a shaped charge is assembled from preformed parts, as mentioned above, deviations from flatness are practically impossible to avoid. Two types predominate: Nonuniform bonding, particularly between propagating charge and main charge, and gaps (air inclusions) between barrier and main or propagating charge.